In the field of computer input devices, it is very common to control the movement of a cursor on a computer screen, or to use that cursor for instruction selection, by employing a device called a “mouse”. A “mouse” is a device electrically connected to the computer and capable of being moved over a surface by the hand of the computer operator. The motion of the mouse over the surface is electronically communicated to the computer to control the movement of a cursor on the screen of the computer. The mouse also includes buttons, which electronically communicate instructions to the computer. In the traditional design, the motion between the mouse and the surface was monitored by the rotation of a rubber ball in the mouse. However, in modern construction, the motion between the surface and the mouse is monitored using an optical sensor which is able to monitor and communicate movement between the mouse and the surface to the computer in a very reliable manner.
Although the typical semiconductor sensor chip, which bears the actual optical sensor electronics, has an area of approximately 4.33 mm2, the practical application of the sensor chip requires packaging technology that currently has a much greater area. Packaging technology refers to containers, supports, and electrical and thermal connections necessary to physically support the chip and electronically connect the chip to the peripheral electronic equipment needed for the chip to perform its function. The current optical mouse sensor packaging technology (DIP of Dual Inline Pin) has an area generally greater than 122.65 mm2. Integrated circuit packaging is an essential part of protecting semiconductor chips from being directly exposed to factors that might cause damage and cause the chip to malfunction, such as heat, air, moisture, and/or vibration. In addition to functioning as a protective shield, packaging serves as a medium to connect the internal circuitry of the semiconductor chip to the outside world. Thus, conventional packaging technology employs an area which is approximately 28 times the area of the actual sensor chip. The relatively large area of the currently necessary packaging technology places a significant size limitation on the designs that can be selected for use of the sensor in the mouse, particularly with regard to alternative designs for mice such as the pen mouse, which is shaped like and held like a pen, or other integrated input devices and pointers.
These and other shortcomings of the prior art optical mouse sensor package have been resolved in a novel manner by the present invention.